* {
    margin: 0;
    padding: 0;
}

html {
    height: 100%;
}

body {
    font-size: 14px;
    background: url("../image/bag.jpg") center center no-repeat;
    background-size: cover;
    height: 100%;
}

a {
    text-decoration: none;
    font-size: 14px;
    color: #fff;
}

ul li, ol li {
    list-style-type: none;
}

.banner {
    width: 1000px;
    height: 400px;
    position: absolute;
    left: 0;
    top: 0;
    right: 0;
    bottom: 0;
    margin: 50px auto;
}

.banner .btn img {
    position: absolute;
    top: 50%;
    margin-top: -22.5px;
    z-index: 4;
}

.banner .left {
    left: 50px;
    cursor: pointer;
}

.banner .right {
    right: 50px;
    cursor: pointer;
}

.banner .img ul li {
    position: absolute;
    top: 100px;
    left: 250px;
    width: 500px;
    height: 200px;
    z-index: -1;
    opacity: 0.1;
    box-shadow: 1px 1px 20px 1px #fff;
}

.banner .img ul li img {
    width: 100%;
    height: 100%;
}

.banner .img ul li.img_first {
    width: 600px;
    height: 300px;
    top: 50px;
    left: 200px;
    z-index: 3;
    opacity: 1;
    box-shadow: 1px 1px 20px 8px #fff;
}

.banner .img ul li.img_second {
    left: 450px;
    z-index: 2;
    opacity: 0.5;
}

.banner .img ul li.img_last {
    left: 50px;
    z-index: 2;
    opacity: 0.5;
}

body .bag {
    position: absolute;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.6);
}